CDF_VARINQ

The CDF_VARINQ function returns a structure containing information about the specified variable in a Common Data Format file.

Syntax

Result = CDF_VARINQ( Id, Variable [, /ZVARIABLE] )

Return Value

The returned structure has the form:

{ IS_ZVAR:0, NAME:"", DATATYPE:"", NUMELEM:0L, $ 
   RECVAR:"", DIMVAR:BYTARR(...) [, DIM:LONARR(...)]} 


Note

The DIM field is included in the structure only if IS_ZVAR is one.

Explanation of the Structure Tags

The following table provides structure tag information.

Table 2-2: CDF_VARINQ Structure Tags
Tag	Description
IS_ZVAR	This field will contain a 1 if the variable is a zVariable or a 0 if it is an rVariable.
NAME	The name of the variable.
DATATYPE	A string describing the data type of the variable. The string has the form `CDF_XXX' where XXX is FLOAT, DOUBLE, EPOCH, UCHAR, etc.
NUMELEM	The number of elements of the data type at each variable value. This is always 1 except in the case of string type variables (CDF_CHAR, CDF_UCHAR).
RECVAR	A string describing the record variance of the variable. This is either the string `VARY' or `NOVARY'.
DIMVAR	An array of bytes. The value of each element is zero if there is no variance with that dimension and one if there is variance. For zero-dimensional CDFs, DIMVAR will have one element whose value is zero.
DIM	An array of longs. The value of each element corresponds to the dimension of the variable. This field is only included in the structure if the variable is a zVariable.

Arguments

Id

The CDF ID, returned from a previous call to CDF_OPEN or CDF_CREATE.

Variable

A string containing the name or an integer containing the index of the variable being inquired.

Keywords

ZVARIABLE

If Variable is a variable ID (as opposed to a variable name) and the variable is a zVariable, set this flag to indicate that the variable ID is a zVariable ID. The default is to assume that Variable is an rVariable ID.

Examples

See the example for CDF_VARGET.

Version History


Pre 4.0	Introduced